The drilling line is reeled over the crown block and traveling block to gain mechanical advantage in a "block and tackle" or "pulley" fashion.
钻井用钢丝绳通过天车和游动滑车以滑轮组的形式获得机械上效益。
The text detailedly introduced crown block, running system, availability work period of bridge girder erection equipment and improve case for precast beams install.
详细介绍了对双导梁式架桥机天车、行走系统、有效工作长度及预制梁安装就位的改进情况。
Conclusions Applying 30% supersaturated potassium oxalate to block dentinal tubule could prevent or reduce crown surface discoloration effectively after front teeth canal therapy.
结论使用30%草酸钾封闭牙本质小管可有效防止及减少前牙根管治疗后牙冠变色。
From the crown sheave, manually pull and reeve the 1 inch Manila rope through the first sheave of the traveling block.
用人力把棕绳从天车轮上拉过来，再穿过第一个游车轮。
From the crown sheave, manually pull and reeve the 1 inch Manila rope through the first sheave of the traveling block.
用人力把棕绳从天车轮上拉过来，再穿过第一个游车轮。
应用推荐